Electron microscopy
 
Synchrotron X-ray Diffraction
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Synchrotron X-ray Diffraction technique provides high intensity and high resolution, and thus inproves the quality of structure determination. However, there is only one-dimensional (1D) intensity information in powder X-ray diffraction pattern and it is not a good technique to determine the three-dimensional (3D) unit cell dimensions especially if a few weak peaks from an unknown impurity phase are present.

Table 4413 lists the comparison between conventional X-ray diffraction and synchrotron X-ray Diffraction.

Table 4413. Comparison between conventional and synchrotron X-ray Diffraction.

  Conventional X-ray diffraction Synchrotron X-ray Diffraction
Intensity Limited intensity High intensity
Wavelength Limited minimum wavelength, thus more absorption by the sample (maximum sample size is limited) Smaller, thus minimize absorption
Samples Need large samples due to limited intensity Can be small samples due to high intensity
Data acquisition Low speed due to limited intensity High speed due to high intensity, thus good for fast in situ processes and unstable compounds
Signal-to-noise Can be low High, thus good for weak features (e.g. impurities, satellite reflections, diffuse scattering)
Resolution Low High, thus good for complex structures with big unit cells, fine peak splitting (phase transitions, decomposition), and peak shapes defined by sample properties (strain, particle size)

 

 

 

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